Spiral container tube



Aug. 25, 1959 c. L. VALLAS 2,901,162

SPIRAL M CONTAINER TUBE Filed July 18, 1955 Eww Fig. 5

INVENTOR.

EHHE'LEE L. VHLLF/E BY *Jqg Q ig ATTORNEYS United States Patent M SPIRAL CONTAINER TUBE Charles L. Vallas, Altadena, Califl, assignor to The Cleveland Container Company, Cleveland, Ohio, a corporation of Ohio Application July 18, 1955, Serial No. 522,438

2 Claims. (Cl. 229-51) This invention, relating as indicated to a spirally wound container tube, is more particularly directed to single body containers formed of a plurality of overlapping plies of paperboard or foil liner in a container tube, which in one embodiment is adapted for use with bakery products which are prepared ready for the oven.

The invention further relates to a sealed container suitable for containing prepared dough bakery products under pressure, said container being structurally adapted for easy opening so that the contents may be readily removed therefrom.

An object of this invention is to provide improvements in container structure which increase the durability of the unit while at the same time facilitating the easy opening thereof.

A further object of this invention is to produce a new type spirally wound tube container for pliable materials held under pressure that may be readily opened.

Another object of this invention is to produce a new method of making and opening a spirally wound single body tube container for release of the materials within the container.

To the accomplishment of the foregoing and related ends said invention then consists of the means hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail one approved means of carrying out the invention, such disclosed means, however, constituting but one of the various ways in which the principles of the invention may be used.

In the drawings:

Fig. 1 is a perspective view of a can with tab ready for removal;

Fig. 2 is a front elevation view of the label ply being uncovered to disclose the perforation line of the outer chip P y;

Fig. 3 is a fragmentary cut-away view in front elevation of the can showing the label ply and the outer chip ply uncovered;

Fig. 4 is a front elevation of the outer and inner plies and the label ply being uncovered to show the sealing, or foil, ply of the interior;

Fig. 5 is an enlarged cross-sectional view of said plies along the line 5-5 of Fig. 1; and

Fig. 6 is a fragmentary view showing the line of demarcation between the outer ply and its perforation line and the inner ply and its butt joint in one version of the invention.

In the art of spirally wound tubular containers it is conventional practice to form a plurality of plies of paperboard either with butt joints or lapped and to form these fully glued to one another to form a tough spirally wound container to hold materials, in some instances, prepared dough for bakery products. These spirally wound tubes are sealed at the ends with a metal end seal, though there may be other types of end sealing means. To open said containers various efforts have been made to provide a weakened section so that the container can be spirally 2,901,162 Patented Aug. 25, 1959 unwound for removal of the contents. Some degree of pressure may be present inside of the sealed container in certain cases, as, for example, the pressure which results when the yeast in food products becomes active due to exposure to room temperatures.

A new type of spiral container tube has been found to be necessary because experience has shown there is considerable waste in connection with breakage of these containers and considerable dissatisfaction in the means for opening them. Said new container is shown in Fig. 1, where 10 is generally the spirally wound container tube and 11 is a metal end seal having a rolled flange 12, and 13 is the lower end seal having a rim 14. The outer ply is more commonly referred to as the label ply designated 15, having a starting point shown at 16, a tab portion shown at 18, with the edge of the label ply being shown as it spirals about the can terminating at the base thereof as indicated at 20.

Fig. 2 shows the same can with the tab 18 pulled back and the label ply 15 covering the outer ply of paperboard or chipboard 21. This outer ply has a line of perfora tions 19 at intervals in a spiral extending from the top of the can or rim 12 to the lower portion at 14, spiralling approximately 360 in the length of the can.

Fig. 3 is a front elevation view showing the label ply 15 having the tab 18 pulled back and the outer ply designated 21 with its perforation line 19 shown on each side of the can. This covers the inner ply, also of paperboard or chipboard fully glued to the outer ply. Said inner ply is shown at 22 and has a butt joint in the plies shown at 23. Said butt joint is approximately parallel to and in the vicinity of the perforation line 19. This provides a tight seam capable of withstanding internal pressures of the order of magnitude of 50 to 60 pounds per square inch with safety. At the same time, by uncovering the label ply 15, the perforation line of the outer ply shown at 19 can be broken by means of a blow or pressure from the hand, as is seen in Fig. 6, and this will break the seal in the can and permit the entire structure to open along the lines of the butt joint 23 and the perforation line 19.

Fig. 4 shows a further view in front elevation of the can with all three of the plies being uncovered disclosing the inner ply which would be a paper material, or possibly a foil such as aluminum, with a large amount of overlap that provides a seal in connection with certain products. This may not be necessary for all materials, but for prepared doughs and the like it provides an inner seal. Said inner ply of foil or the like would be of substantially lesser thickness than that of the inner and outer paperboard plies. This inner ply would be fully glued to the inner paperboard or chipboard ply. Said latter ply is shown particularly at 24.

This combination of parts is shown in an expanded fragmentary view in connection with Fig. 5. The top of the can is shown at 11 having a rim 12 to seal the spirally wound tubular container. The label ply is relatively thin, as shown at 15, and this may be printed or otherwise marked. The outer ply is shown at 21 fully glued and adjacent to said label ply. There is a perforation line as shown at 19. Said perforation line is adjacent to the butt joint of the inner ply 22, said butt joint being shown at 23. On the inside of the can is a sealing ply of foil or the like, said ply being shown at 24.

As an example of one of these containers, the following might be given for a prepared dough container. Said can might be 2 inches in diameter and 5 inches long, and the outer ply or label ply might be foil .00035 inch thick, which could well be sulphite backed paper foil, put on in strips about 4% inches wide with inch overlap and fully glued except for the tab. The outer ply of paperboard would be the second ply in from the exterior. This would be .019 inch of chipboard and would generally be 3 formed with a butt joint. The third ply from the exterior hereinbefore referred to as the inner ply would be of the same chipboard with an outer newsline finish. This would be formed with a butt joint. The butt joint would be somewhat adjacent to the perforation that would be formed in the second ply.

It will be appreciated that the relationship of the perforations to the butt joint of the inner ply may vary depending upon the length and diameter of the container and upon the type of contents or pressure within the container. With specific reference to prepared biscuit dough cans, it has been found that good results are achieved when the butt joint is within Vs inch of the perforation line. However, for various other types of containers having different diameters, type of contents and the like, the relationship of the spacing of the butt joint to the perforation line in the outer chipboard ply would normally not exceed 1 inch. In the embodiment shown for a prepared biscuit dough container, the apertures in the perforation line of the outer ply are about inch long and there is about /8 inch connection between the apertures.

The inner ply is a sulphite backed paper foil about .00035 inch in thickness with some amount of overlap. All of the plies are fully glued to one another except for the tab on the label ply, although it will be obvious that other means for making an end of the label ply available for unwinding may be used.

For opening the can, the strip of the label ply, such as the tab which is unglued, is pulled and unwound, thus removing the outer label and uncovering the perforation line of the outer chipboard ply. A blow or pressure exerted on and along the perforation line of the outer ply, as illustrated in Fig. 6, will break the sealing relationship between the plies and bring about an opening between the inner and outer chipboard plies along the perforation line and butt joint of these two plies. Twisting of the ends of the can in opposite directions will then further open the container along the indicated break or separation line so that the contents can be removed. It will be appreciated, of course, that the lapped inner sealing ply of the container will not be an impediment to the opening of the container once the major intermediate structural chipboard layers are split.

One of the many advantages possessed by the container embodying the instant invention is that it is considerably easier to manufacture, and it is found to be very much stronger in that all of the plies of the container are fully glued one to the other. Heretofore, prepared dough containers have employed one or more non-glued plies to facilitate the opening of the can and this has, of course, weakened the structural rigidity of the container wall. Another advantage is the elimination of a circumferential skive cut heretofore used in certain containers of this type. Those skilled in the art know that controlling the depth of a skive cut through an outer layer of chipboard is extremely diflicult and a great deal of waste has been encountered when the skive cut through the outer plies so weakened the inner plies that jarring of the containers during handling caused the containers to break open along the skive cut. It will also be apparent that in the case of biscuit dough containers, as the can is spirally opened, biscuits at both ends of the can can be readily removed as the container unfolds.

It is possible that in connection with certain products it may be desirable to have more than one perforation line spiralling around the can in the paperboard outer layer. Under some conditions it may not be necessary to have an inner sealing ply and an outer label ply. The principal combination is the inner and outer plies fully glued to one another in which there is a perforated line weakening the outer ply and a connection like a butt joint on the inner ply.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presentiembodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

1 claim:

1. In a spirally wound, multi-ply container tube having at least a semi-rigid wall construction, two adjacent independently flexible ply strips wound one upon the other and in the same direction, each of said strips being wound with its edges in homogeneous abutment and presenting internal and external lateral surfaces of substantially uniform diameter, the abutting edges of one ply being spaced axially apart from the edges of the other ply to impart maximum rigidity to the container tube, the major portion of the inner surface of the outer of said ply strips and the major portion of the outer surface of the inner of said ply strips adhering one to the other in static bonded engagement, the spirally extending zonular area in which lie the abutting edges of said inner ply being included in said major portion, the outer of said ply strips having formed therein and spaced from the edges thereof a spirally extending weakened zone of greater than hernispherical order and primarily circumferential in direction formed by a series of perforations in the ply disposed in adjacent offset substantial parallelism with the abutting edges of the inner ply, a sealing ply strip of substantially lesser thickness than the said inner and outer plies disposed in contact with said inner ply and substantially fully bonded thereto, and a second sealing ply strip adhesively secured to said outer ply strip and disposed to have thereon instructions and labeling, said second sealing ply being spirally wound in the same direction as the inner and outer plies, the bond between said second sealing ply and said outer ply strip being weaker than the bond between said outer ply strip and said inner ply strip, rigid closure caps at each end of the container with annular flange portions thereof seamed over the ends of the tubular container wall and holding the same in circumferential compression and radial tension, and means pro vided on said label to facilitate unwrapping thereof from said outer ply strip whereby to expose said spirally extending series of perforations such that when an inwardly directed force is applied along at least a portion of the perforation line, the surface bond between the plies in the zone adjacent thereto and between the abutting edge of the inner ply will be broken, permitting the container to be opened along the thus weakened spirally extending zone.

2. A device as defined in claim 1 in which said means to facilitate unwrapping of the second sealing ply from the outer ply strip includes a tab on one end of said second sealing ply, said tab lying loosely against a lateral surface of said outer ply, and adapted to be pulled away from said outer ply strip to uncover at least a portion of the perforation zone contained within the said outer ply strip.

References Cited in the file of this patent UNITED STATES PATENTS 1,936,417 Ware Nov. 21, 1933 2,051,923 Vogt Aug. 25, 1936 2,148,480 Larsh Feb. 28, 1939 2,555,380 Stuart et al. June 5, 1951 2,709,548 Gilbert May 31, 1955 2,753,104 Wagner July 3, 1956 2,793,126 Fienup May 21, 1957 2,793,127 Geist May 21, 1957 2,800,267 ONeil July 23, 1957 

